To avoid collision between vehicles, there has been proposed a technique in which information is received from an adjacent vehicle, data related to an own vehicle is sent to the adjacent vehicle, prediction of movement trajectories of the vehicle and the adjacent vehicle as well as collection of information on a situation surrounding the vehicle is performed on the basis of the received information, the data related to the vehicle, the current own position and the current position of the adjacent vehicle, and data indicating dangerous situations, and in danger of a collision, a signal is transmitted to a driver and the adjacent vehicle (for example, see Published Japanese Translation of PCT International Publication for Patent Application (Kohyo) No. 2009-537367).